Telephone receiver



UNE

arras FlillQE.

LlJRY KCI-I, 0F JAMAICA, AND FRIEDRICH H. N. W'OHLERS, OF HEMISTEAD, NEW i YORK, ASSIGNORS '110 DICTOGRAPH PRODUCTS CORPORATION, A CORPORATION 0l? VIRGINIA TELEPHONE RECEIVER.

Application filed January 8, 1924..

To au 1o/Lomi?? may concern .1

Be it known that we, HENRY Koor-r and Fnmnnrorr ll. N. Wortmans, citizens of the United States, residing at Jamaica and Hempstead, respectively, in the county oit Queens and State or" New York, have invented certain new and useful lmprovements in Telephone Receivers, of: which the 'following is a lull, clear, and exact desiription.

|This invention relates to telephone receivers, particularly of the type commonly employed in radiotelephone and telegraph. receiving sets and popularly -known as loud speakers. 'The invention is in the nature oll an improvement upon `the type of loud speaker disclosed in copending applications ot' Henry Koch, Serial No. 628,709, iiled March 30, 1923, and Serial No. 661,596, tiled September 8, 1923. In this type of .loud speaker, the-volume of sound may be varied by varying the influence upon the diaphragm or' an electromagnetic actuating unit and this invention comprehends means for simpli'fying or facilitating the initial adjustment of the means for varying the inlluence of the electromagnetic unit upon. the diaphragm.

An object oit the invention is to provide an improved telephone receiver construction, in which the initial adjustment of the volume varying means may be quickly and easily elected in a simple manner, which will, at the same time, be relatively simple in construction and easil assembled, and which will readily permit subsequent ad justments of the volume varying means in oase such subsequent adjustment becomes necessary. Other objects and advantages will be apparent from the following; description of an embodiment of the invention, and the novel 'features will be particularly pointed out hereinafter in claims.

1n the accompanying drawing:

Fig. 1 is a sectional elevation through a loud speaker constructed in accordance with the invention;

Fig, f2 is a transverse section of the same,

taken substantially along the line 2-'2 of Figure 1; and

Figi'. 3 is a sectional elevation of a portion ot' the speaker, the section being taken substantially along;` the line 3-3 of Figure 2.

In the illustrated embodiment of they invention, an amplifying horn 1 is supported upon a suitable hollow base 2, with the small Serial No, 684,952.

end ot the amplifier 1 communicating through an aperture 3 with the interior of the support orbase Q. plate 4 is secured against the inner face of the wall of the base having the aperture 3, and is provided with an aperture 5 aligned with the aperture 3. A cup-shaped casing 6 is secured with its open end against the plate 4, and a diaphragm 7 is clamped between the open end of the casing; 6 and the plate l, suitable gaskets being disposed upon opposite faces of the diaphragm around its periphery so as to permit or". 'free vibration of the diaphragm. A second cup-shaped casing 8 is disposed within and slidable in the casing 6, with its open end at the open end of the casing 6.

The casing S is provided with a stud 9 p extending freely rearwardly through an aperture l() of the casing 6, and the outer end ot' the stud is threaded., A gear 11 is threaded upon the outer threaded end `ot' the stud 9, and one or more Washers 12 may be disposed between the gear 11 and the outer face of the wall ot' the casing 6 through which the stud passes. A suitable spring` 13 is disposed between the inner end or the casing 8 and the abutting` wall ofthe casing 6, so as to constantly' and yieldingly urge the casing 8 toward the diaphragm and draw the gear 11 toward the casing 6. The gear 11, however, limits thc movement ot the casing,- 8 under the influence of the spring 13. ln the embodiment illustrated, the spring 13 is in the nature or a leaf spring with a central aperture through which the stud 9 passes. A pin 14 within the casing 6 projects through an aperture in the spring and also enters an aperture in the inner end Wall ol. the casing 8, and thus 'serves to keep both casing 6 and the spring 13 from rotating within the casing 6.

An electromagnetic vactuating unit l5,

having spaced pole pieces 16, is mounted in p any suitable manner within the casing 8 so as to move therewith toward and from the diaphragm 7. Suitable circuit wires 17 lead from the electromagnetic unit 15 through an aperture 18 in the base or support for 1ncorporationin any actuating circuit.'

A. shaft 19 is rotatably mounted in the base or support 2 and carries, upon 1 ts o uter end, an actuating buttonQO and an indicating dial 21, by means olf-which the shaftr .may be rotated to various desired angular positions. The. inner end portion 22 of the ing a secondgear meshing with the first gear, means' for operating said gear includgear, a shaft upon which the second gear is keyed so as to slide thereon 4and rotate therewith, a spring device for yieldingly pressing the second gear en'dwise along the shaft, and means ior limiting endivise movement of the second gear by the spring device beyond a position in which it meshes with 'the iirst gear, said spring device yielding to permit. lmovement o the second gear away from the limiting means and out of mesh with the rstgear in order to enable an initial settingrotl the first gear independently of the second gear.

fl. ln a telephone receiver, a diaphragm, an electromagnetic actuating device for said diaphragm, means by which the influence of the actuating device upon 'the diaphragm may be varied, and including an operating gear, means for operating said gear including a second gear meshing with the first gear, a shaft upon which the second gear is keyed so as to slide thereon and rotate therewith, a spring device for yieldingly pressing the second gear endwise along the shaft, said shaft having thereon a shoulder against which said second gear is yieldingly pressed when in mesh lwith said firstgear, said spring device yielding to permit movement of the second gear away from the shoulder when the second gear is shifted ont ci' mesh with the first gear to enable an initial setting ot the iirst gear independently of the second gear.

5. ln a telephone receiver, a diaphragm, a casing at one end of which the diaphragm is mounted, an electromagnetic device mounted in said casing and movable toward and from the diaphragm, a gear in threaded connection with the. device and acting against the casing soithat when the gear rotated in one direction the device will be shifted in one direction relatively to the diaphragm, a spring device for shifting the electromagnetic device in the opposite direcn tion when the gear is rotated in the opposite direction to release the electromagnetic device, a shaft bearing in said casing and having a shoulder thereon, a pinion lreyed to the shaft for movement toward and frein the shoulder, said pinion meshing with the gear when against the shoulder and out ci mesh therewith when shifted away from said shoulder, means for yieldingly holding the said pinion against said shoulder and yielding to permit demeshing of the pinion and gear and thus enable an initial setting or' the gear independently of the pinion and shaft, and an operating button on said shaft to enable its manual oper-- ation.

6. lfn av telephone receiver, a diaphragm, an electromagnetic actuating device for said diaphragm movable relative thereto fior varying its influence thereon, means including a gear for producing such relative movement, a pinionv meshino' with and drivmg said gear, means by 'Weich the 'pinion may be rotated, and means whereby 'the operative connection between said last named` means and the gear through the pinion may be broken to permit an initial setting to be given to 'the 'diaphragm and its actuating device.

lin Witness whereof, we hereunto salas' scribe our signatures.

vernaar Koen.

FRHEDRCH H, N. VHLERS. 

